摘要 |
<p>PCT No. PCT/GB87/00883 Sec. 371 Date Jul. 21, 1989 Sec. 102(e) Date Jul. 21, 1989 PCT Filed Dec. 7, 1987 PCT Pub. No. WO88/04228 PCT Pub. Date Jun. 16, 1988.Fibrous network structures are produced within liquid polymer resins by passing the fiber-containing resin along a channel having a plurality of sets of flow modifying elements which establish a regulated succession of velocity profiles for the principal flow direction and the two directions perpendicular thereto. The individual velocity profiles persist over distances which are small compared to the channel dimension over which they are established and are such that there is substantially no net deviation from the principal flow direction. The velocity profiles superimpose on each other to cause rotation and sliding of the fibers so that a coherent network structure is built up which persists through extrusion dies and molds into the solid state. By means of a large number of touches per fiber the structures thereby established confer efficient mechanical reinforcing properties and enhanced thermal properties on the polymer composition.</p> |